A temperature analysis method based on defects of cable protective layers

Abstract The safety and stability of power systems heavily depend on the performance of cables. However, excessive heat accumulation during operation causes fatigue damage to materials such as insulation layers, which may lead to severe incidents such as fires. In this paper, a temperature analysis method for underground cable defects of protective layers is proposed, using a three-phase model to simulate temperature variations in cables with different defects. Based on the observation that cable temperatures increase under different operating current conditions, the temperature field distribution is analyzed for cables with defects in the isolation sheath and shielding layer, showing the temperature increases with the severity of defects in the isolation sheath, while it decreases with the increasing severity of defects in the shielding layer. Elevated temperatures exacerbate the deterioration of defects, and although the temperature-related issues in the shielding layer are relatively minor, the potential risks to electrical safety remain unmitigated. Both types of defects lead to fire hazards, analyzing the temperature field critical for ensuring both the safety of power systems and fire prevention.